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Simulation of the land surface temperature from moon-based Earth observations EI Scopus SCIE
期刊论文 | 2019 , 63 (2) , 826-839 | Advances in Space Research
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Abstract :

The land surface temperature (LST) is a key parameter for the Earth's energy balance. As a natural satellite of the Earth, the orbital of the moon differs from that of current Earth observation satellites. It is a new way to measure the land surface temperature from the moon and has many advantages compared with artificial satellites. In this paper, we present a new method for simulating the LST measured by moon-based Earth observations. Firstly, a modified land-surface diurnal temperature cycle (DTC) method is applied to obtain the global LST at the same coordinated universal time (UTC) using the Moderate Resolution Imaging Spectroradiometer (MODIS) LST products. The lunar elevation angles calculated using the ephemeris data (DE405) from the Jet Propulsion Laboratory (JPL) were then applied to simulate the Earth coverage observed from the moon. At the same time, the modified DTC model was validated using in situ data, MODIS LST products, and the FengYun-2F (FY-2F) LST, respectively. The results show that the fitting accuracy (root-mean-square error, RMSE) of the modified DTC model is not greater than 0.72 °C for eight in situ stations with different land cover types, and the maximum fitting RMSE of the modified model is smaller than that of current DTC models. By the comparison of the simulated LST with MODIS and FY-2F LST products, the errors of the results were feasible and accredited, and the simulated global LST has a reasonable spatiotemporal distribution and change trend. The simulated LST data can therefore be used as base datasets to simulate the thermal infrared imagery from moon-based Earth observations in future research. © 2018

Keyword :

Coordinated universal time Diurnal temperature cycles Earth observation satellites Earth observations Land surface temperature Moderate resolution imaging spectroradiometer Simulation Spatiotemporal distributions

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GB/T 7714 Nie, Chenwei , Liao, Jingjuan , Shen, Guozhuang et al. Simulation of the land surface temperature from moon-based Earth observations [J]. | Advances in Space Research , 2019 , 63 (2) : 826-839 .
MLA Nie, Chenwei et al. "Simulation of the land surface temperature from moon-based Earth observations" . | Advances in Space Research 63 . 2 (2019) : 826-839 .
APA Nie, Chenwei , Liao, Jingjuan , Shen, Guozhuang , Duan, Wentao . Simulation of the land surface temperature from moon-based Earth observations . | Advances in Space Research , 2019 , 63 (2) , 826-839 .
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Improved search for solar chameleons with a GridPix detector at CAST SCIE
期刊论文 | 2019 , (1) | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
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Abstract :

We report on a new search for solar chameleons with the CERN Axion Solar Telescope (CAST). A GridPix detector was used to search for soft X-ray photons in the energy range from 200 eV to 10 keV from converted solar chameleons. No significant excess over the expected background has been observed in the data taken in 2014 and 2015. We set an improved limit on the chameleon photon coupling, beta(gamma) less than or similar to 5.7 x 10(10) for 1 < beta(m) < 10(6) at 95% C.L. improving our previous results by a factor two and for the first time reaching sensitivity below the solar luminosity bound for tachocline magnetic fields up to 12.5 T.

Keyword :

particle physics - cosmology connection modified gravity solar physics dark energy experiments

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GB/T 7714 Anastassopoulos, V , Aune, S. , Barth, K. et al. Improved search for solar chameleons with a GridPix detector at CAST [J]. | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS , 2019 , (1) .
MLA Anastassopoulos, V et al. "Improved search for solar chameleons with a GridPix detector at CAST" . | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS 1 (2019) .
APA Anastassopoulos, V , Aune, S. , Barth, K. , Belov, A. , Braueninger, H. , Cantatore, G. et al. Improved search for solar chameleons with a GridPix detector at CAST . | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS , 2019 , (1) .
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SPHERE dynamical and spectroscopic characterization of HD142527B SCIE
期刊论文 | 2019 , 622 | ASTRONOMY & ASTROPHYSICS
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Abstract :

Aims. HD142527 is one of the most frequently studied Herbig Ae/Be stars with a transitional disk that hosts a large cavity that is up to about 100 au in radius. For this reason, it has been included in the guaranteed time observation (GTO) SpHere INfrared survey for Exoplanets (SHINE) as part of the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) at the Very Large Telescope (VLT) in order to search for low-mass companions that might explain the presence of the gap. SHINE is a large survey within about 600 young nearby stars are observed with SPHERE with the aim to constrain the occurrence and orbital properties of the giant planet population at large (>5 au) orbital separation around young stars. Methods. We used the IRDIFS observing mode of SPHERE (IRDIS short for infrared dual imaging and spectrograph plus IFS or integral field spectrograph) without any coronagraph in order to search for and characterize companions as close as 30 mas of the star. Furthermore, we present the first observations that ever used the sparse aperture mask (SAM) for SPHERE both in IRDIFS and IRDIFS_EXT modes. All the data were reduced using the dedicated SPHERE pipeline and dedicated algorithms that make use of the principal component analysis (PCA) and reference differential imaging (RDI) techniques. Results. We detect the accreting low-mass companion HD142527B at a separation of 73 mas (11.4 au) from the star. No other companions with mass greater than 10 M-J are visible in the field of view of IFS (similar to 100 au centered on the star) or in the IRDIS field of view (similar to 400 au centered on the star). Measurements from IFS, SAM IFS, and IRDIS suggest an M6 spectral type for HD142527B, with an uncertainty of one spectral subtype, compatible with an object of M = 0.11 +/- 0.06 M-circle dot and R = 0.15 +/- 0.07 R-circle dot. The determination of the mass remains a challenge using contemporary evolutionary models, as they do not account for the energy input due to accretion from infalling material. We consider that the spectral type of the secondary may also be earlier than the type we derived from IFS spectra. From dynamical considerations, we further constrain the mass to 0.26(-0.14)(+0.16) , which is consistent with both our spectroscopic analysis and the values reported in the literature. Following previous methods, the lower and upper dynamical mass values correspond to a spectral type between M2.5 and M5.5 for the companion. By fitting the astrometric points, we find the following orbital parameters: a period of P = 35 137 yr; an inclination of i = 121 130 degrees, a value of Omega = 124 135 degrees for the longitude of node, and an 68% confidence interval of similar to 18-57 au for the separation at periapsis. Eccentricity and time at periapsis passage exhibit two groups of values: similar to 0.2-0.45 and similar to 0.45-0.7 for e, and similar to 2015-2020 and similar to 2020-2022 for T-0. While these orbital parameters might at first suggest that HD142527B is not the companion responsible for the outer disk truncation, a previous hydrodynamical analysis of this system showed that they are compatible with a companion that is able to produce the large cavity and other observed features.

Keyword :

stars: individual: HD142527 instrumentation: high angular resolution techniques: imaging spectroscopy protoplanetary disks stars: formation

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GB/T 7714 Claudi, R. , Maire, A. -L. , Mesa, D. et al. SPHERE dynamical and spectroscopic characterization of HD142527B [J]. | ASTRONOMY & ASTROPHYSICS , 2019 , 622 .
MLA Claudi, R. et al. "SPHERE dynamical and spectroscopic characterization of HD142527B" . | ASTRONOMY & ASTROPHYSICS 622 (2019) .
APA Claudi, R. , Maire, A. -L. , Mesa, D. , Cheetham, A. , Fontanive, C. , Gratton, R. et al. SPHERE dynamical and spectroscopic characterization of HD142527B . | ASTRONOMY & ASTROPHYSICS , 2019 , 622 .
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Seasonal variation of the underground cosmic muon flux observed at Daya Bay SCIE Scopus
期刊论文 | 2018 , (1) | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
An, F. P. | Balantekin, A. B. | Band, H. R. | Bishai, M. | Blyth, S. | Cao, D. | Cao, G. F. | Cao, J. | Chan, Y. L. | Chang, J. F. | Chang, Y. | Chen, H. S. | Chen, Q. Y. | Chen, S. M. | Chen, Y. X. | Chen, Y. | Cheng, J. | Cheng, Z. K. | Cherwinka, J. J. | Chu, M. C. | Chukanov, A. | Cummings, J. P. | Ding, Y. Y. | Diwan, M. V. | Dolgareva, M. | Dove, J. | Dwyer, D. A. | Edwards, W. R. | Gill, R. | Gonchar, M. | Gong, G. H. | Gong, H. | Grassi, M. | Gu, W. Q. | Guo, L. | Guo, X. H. | Guo, Y. H. | Guo, Z. | Hackenburg, R. W. | Hans, S. | He, M. | Heeger, K. M. | Heng, Y. K. | Higuera, A. | Hsiung, Y. B. | Hu, B. Z. | Hu, T. | Huang, E. C. | Huang, H. X. | Huang, X. T. | Huber, P. | Huo, W. | Hussain, G. | Jaffe, D. E. | Jen, K. L. | Jetter, S. | Ji, X. P. | Ji, X. L. | Jiao, J. B. | Johnson, R. A. | Jones, D. | Kang, L. | Kettell, S. H. | Khan, A. | Kohn, S. | Kramer, M. | Kwan, K. K. | Kwok, M. W. | Kwok, T. | Langford, T. J. | Lau, K. | Lebanowski, L. | Lee, J. | Lee, J. H. C. | Lei, R. T. | Leitner, R. | Li, C. | Li, D. J. | Li, F. | Li, G. S. | Li, Q. J. | Li, S. | Li, S. C. | Li, W. D. | Li, X. N. | Li, X. Q. | Li, Y. F. | Li, Z. B. | Liang, H. | Lin, C. J. | Lin, G. L. | Lin, S. | Lin, S. K. | Lin, Y. -C. | Ling, J. J. | Link, J. M. | Littenberg, L. | Littlejohn, B. R. | Liu, J. L. | Liu, J. C. | Loh, C. W. | Lu, C. | Lu, H. Q. | Lu, J. S. | Luk, K. B. | Ma, X. Y. | Ma, X. B. | Ma, Y. Q. | Malyshkin, Y. | Caicedo, D. A. Martinez | McDonald, K. T. | McKeown, R. D. | Mitchell, I. | Nakajima, Y. | Napolitano, J. | Naumov, D. | Naumova, E. | Ngai, H. Y. | Ochoa-Ricoux, J. P. | Olshevskiy, A. | Pan, H. -R. | Park, J. | Patton, S. | Pec, V. | Peng, J. C. | Pinsky, L. | Pun, C. S. J. | Qi, F. Z. | Qi, M. | Qian, X. | Qiu, R. M. | Raper, N. | Ren, J. | Rosero, R. | Roskovec, B. | Ruan, X. C. | Sebastiani, C. | Steiner, H. | Sun, J. L. | Tang, W. | Taychenachev, D. | Treskov, K. | Tsang, K. V. | Tull, C. E. | Viaux, N. | Viren, B. | Vorobel, V. | Wang, C. H. | Wang, M. | Wang, N. Y. | Wang, R. G. | Wang, W. | Wang, X. | Wang, Y. F. | Wang, Z. | Wang, Z. | Wang, Z. M. | Wei, H. Y. | Wen, L. J. | Whisnant, K. | White, C. G. | Whitehead, L. | Wise, T. | Wong, H. L. H. | Wong, S. C. F. | Worcester, E. | Wu, C. -H. | Wu, Q. | Wu, W. J. | Xia, D. M. | Xia, J. K. | Xing, Z. Z. | Xu, J. L. | Xu, Y. | Xue, T. | Yang, C. G. | Yang, H. | Yang, L. | Yang, M. S. | Yang, M. T. | Yang, Y. Z. | Ye, M. | Ye, Z. | Yeh, M. | Young, B. L. | Yu, Z. Y. | Zeng, S. | Zhan, L. | Zhang, C. | Zhang, C. C. | Zhang, H. H. | Zhang, J. W. | Zhang, Q. M. | Zhang, X. T. | Zhang, Y. M. | Zhang, Y. X. | Zhang, Y. M. | Zhang, Z. J. | Zhang, Z. Y. | Zhang, Z. P. | Zhao, J. | Zhou, L. | Zhuang, H. L. | Zou, J. H.
WoS CC Cited Count: 1
Abstract&Keyword Cite

Abstract :

The Daya Bay Experiment consists of eight identically designed detectors located in three underground experimental halls named as EH1, EH2, EH3, with 250, 265 and 860 meters of water equivalent vertical overburden, respectively. Cosmic muon events have been recorded over a two-year period. The underground muon rate is observed to be positively correlated with the effective atmospheric temperature and to follow a seasonal modulation pattern. The correlation coefficient alpha, describing how a variation in the muon rate relates to a variation in the effective atmospheric temperature, is found to be alpha(EH1) = 0 : 362 +/- 0 : 031, alpha(EH2) = 0.433 +/- 0.038 and alpha(EH3) = 0.641 +/- 0.057 for each experimental hall.

Keyword :

cosmic ray experiments neutrino experiments neutrino detectors

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GB/T 7714 An, F. P. , Balantekin, A. B. , Band, H. R. et al. Seasonal variation of the underground cosmic muon flux observed at Daya Bay [J]. | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS , 2018 , (1) .
MLA An, F. P. et al. "Seasonal variation of the underground cosmic muon flux observed at Daya Bay" . | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS 1 (2018) .
APA An, F. P. , Balantekin, A. B. , Band, H. R. , Bishai, M. , Blyth, S. , Cao, D. et al. Seasonal variation of the underground cosmic muon flux observed at Daya Bay . | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS , 2018 , (1) .
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Research on navigation of satellite constellation based on an asynchronous observation model using X-ray pulsar EI SCIE Scopus
期刊论文 | 2018 , 61 (3) , 787-798 | ADVANCES IN SPACE RESEARCH
WoS CC Cited Count: 1 SCOPUS Cited Count: 1
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Abstract :

Pulsar navigation is a promising navigation method for high-altitude orbit space tasks or deep space exploration. At present, an important reason for restricting the development of pulsar navigation is that navigation accuracy is not high due to the slow update of the measurements. In order to improve the accuracy of pulsar navigation, an asynchronous observation model which can improve the update rate of the measurements is proposed on the basis of satellite constellation which has a broad space for development because of its visibility and reliability. The simulation results show that the asynchronous observation model improves the positioning accuracy by 31.48% and velocity accuracy by 24.75% than that of the synchronous observation model. With the new Doppler effects compensation method in the asynchronous observation model proposed in this paper, the positioning accuracy is improved by 32.27%, and the velocity accuracy is improved by 34.07% than that of the traditional method. The simulation results show that without considering the clock error will result in a filtering divergence. (C) 2017 COSPAR. Published by Elsevier Ltd.

Keyword :

Asynchronous observation model Doppler effects Modified Kalman filtering Pulsar navigation

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GB/T 7714 Guo, Pengbin , Sun, Jian , Hu, Shuling et al. Research on navigation of satellite constellation based on an asynchronous observation model using X-ray pulsar [J]. | ADVANCES IN SPACE RESEARCH , 2018 , 61 (3) : 787-798 .
MLA Guo, Pengbin et al. "Research on navigation of satellite constellation based on an asynchronous observation model using X-ray pulsar" . | ADVANCES IN SPACE RESEARCH 61 . 3 (2018) : 787-798 .
APA Guo, Pengbin , Sun, Jian , Hu, Shuling , Xue, Ju . Research on navigation of satellite constellation based on an asynchronous observation model using X-ray pulsar . | ADVANCES IN SPACE RESEARCH , 2018 , 61 (3) , 787-798 .
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Evolving ONe WD plus He star systems to intermediate-mass binary pulsars SCIE Scopus
期刊论文 | 2018 , 477 (1) , 384-391 | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
WoS CC Cited Count: 1 SCOPUS Cited Count: 1
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Abstract :

It has been suggested that accretion-induced collapse (AIC) is a non-negligible path for the formation of the observed neutron stars (NSs). An ONe white dwarf (WD) that accretes material from a He star may experience AIC process and eventually produce intermediate mass binary pulsars (IMBPs), named as the ONe WD+He star scenario. Note that previous studies can only account for part of the observed IMBPs with short orbital periods. In this work, we investigate the evolution of about 900 ONe WD+He star binaries to explore the distribution of IMBPs. We found that the ONe WD+He star scenario could form IMBPs including pulsars with 5-340 ms spin periods and 0.75-1.38 M-circle dot WD companions, in which the orbital periods range from 0.04 to 900 d. Compared with the 20 observed IMBPs, this scenario can cover the parameters of 13 sources in the final orbital period WD mass plane and the Corbet diagram, most of which have short orbital periods. We found that the ONe WD+He star scenario can explain almost all the observed IMBPs with short orbital periods. This work can well match the observed parameters of PSR J1802-2124 (one of the two precisely observed IMBPs), providing a possible evolutional path for its formation. We also speculate that the compact companion of HD 49798 (a hydrogen depleted sdO6 star) may be not a NS based on this work.

Keyword :

stars: evolution stars: neutron white dwarfs binaries: close supernovae: general

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GB/T 7714 Liu, D. , Wang, B. , Chen, W. et al. Evolving ONe WD plus He star systems to intermediate-mass binary pulsars [J]. | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY , 2018 , 477 (1) : 384-391 .
MLA Liu, D. et al. "Evolving ONe WD plus He star systems to intermediate-mass binary pulsars" . | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 477 . 1 (2018) : 384-391 .
APA Liu, D. , Wang, B. , Chen, W. , Zuo, Z. , Han, Z. . Evolving ONe WD plus He star systems to intermediate-mass binary pulsars . | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY , 2018 , 477 (1) , 384-391 .
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Thermal performance of liquid hydrogen tank in reduced gravity EI SCIE Scopus
期刊论文 | 2018 , 62 (5) , 957-966 | ADVANCES IN SPACE RESEARCH
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Abstract :

Fluid temperature stratification is significant to the safe operation of space storage tanks. A calculation model, accounting for the liquid-vapor phase change, is developed to investigate the thermal physical process in a liquid hydrogen (LH2) tank in reduced gravity. Viscous flow is considered in calculation model with Ra ranging from 0.1 to 10(5) to ensure the continuity of natural convection. The stratified layer parameters, the tank pressure rise, and the interface phase change are studied respectively. Influences of the initial liquid height, the initial ullage temperature and the tank wall heat flux on the development of thermal stratification are estimated. The results show that the stratified layer thickness rises with the initial liquid height. While the initial liquid height is large, it costs more time for the wholly development of fluid thermal stratification. Largely influenced by the temperature of the stratified layer, both tank pressure and phase change capacity increase with the initial liquid height. It seems that the initial ullage temperature has a weak effect on the development of fluid thermal stratification. Both the tank pressure and the phase change quality increase with the initial ullage temperature. The external tank wall heat flux promotes the development of thermal stratification. The stratified layer has a larger thickness and develops faster for the larger heat flux. Both tank pressure and phase change capacity increase with the external heat flux. Meanwhile, the intersection point exists between any two profiles. (C) 2018 COSPAR. Published by Elsevier Ltd. All rights reserved.

Keyword :

Constant wall heat flux Liquid hydrogen Thermal performance Reduced gravity

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GB/T 7714 Liu, Zhan , Zhou, Guoqing , Li, Yanzhong et al. Thermal performance of liquid hydrogen tank in reduced gravity [J]. | ADVANCES IN SPACE RESEARCH , 2018 , 62 (5) : 957-966 .
MLA Liu, Zhan et al. "Thermal performance of liquid hydrogen tank in reduced gravity" . | ADVANCES IN SPACE RESEARCH 62 . 5 (2018) : 957-966 .
APA Liu, Zhan , Zhou, Guoqing , Li, Yanzhong , Gao, Penghui . Thermal performance of liquid hydrogen tank in reduced gravity . | ADVANCES IN SPACE RESEARCH , 2018 , 62 (5) , 957-966 .
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The core-degenerate scenario for the progenitors of Type Ia supernovae SCIE Scopus
期刊论文 | 2017 , 464 (4) , 3965-3971 | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | IF: 5.194
WoS CC Cited Count: 4 SCOPUS Cited Count: 4
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Abstract :

The origin of the progenitors of Type Ia supernovae (SNe Ia) is still uncertain. The core-degenerate (CD) scenario has been proposed as an alternative way for the production of SNe Ia. In this scenario, SNe Ia are formed at the final stage of common-envelope evolution from a merger of a carbon-oxygen white dwarf (CO WD) with the CO core of an asymptotic giant branch companion. However, the birthrates of SNe Ia from this scenario are still not well determined. In this work, we performed a detailed investigation on the CD scenario based on a binary population synthesis approach. The SN Ia delay times from this scenario are basically in the range of 90-2500 Myr, mainly contributing to the observed SNe Ia with short and intermediate delay times, although this scenario can also produce some old SNe Ia. Meanwhile, our work indicates that the Galactic birthrates of SNe Ia from this scenario are not more than 20 per cent of total SNe Ia due to more careful treatment of mass transfer. Although the SN Ia birthrates in this work are lower than those in Ilkov & Soker, the CD scenario cannot be ruled out as a viable mechanism for the formation of SNe Ia. Especially, SNe Ia with circumstellar material from this scenario contribute to 0.7-10 per cent of total SNe Ia, which means that the CD scenario can reproduce the observed birthrates of SNe Ia like PTF 11kx. We also found that SNe Ia happen systemically earlier for a high value of metallicity and their birthrates increase with metallicity.

Keyword :

stars: evolution supernovae: general white dwarfs binaries: close

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GB/T 7714 Wang, B. , Zhou, W. -H. , Zuo, Z. -Y. et al. The core-degenerate scenario for the progenitors of Type Ia supernovae [J]. | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY , 2017 , 464 (4) : 3965-3971 .
MLA Wang, B. et al. "The core-degenerate scenario for the progenitors of Type Ia supernovae" . | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 464 . 4 (2017) : 3965-3971 .
APA Wang, B. , Zhou, W. -H. , Zuo, Z. -Y. , Li, Y. -B. , Luo, X. , Zhang, J. -J. et al. The core-degenerate scenario for the progenitors of Type Ia supernovae . | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY , 2017 , 464 (4) , 3965-3971 .
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Stability of multiplanetary systems in star clusters SCIE
期刊论文 | 2017 , 470 (4) , 4337-4353 | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | IF: 5.194
WoS CC Cited Count: 6
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Abstract :

Most stars form in star clusters and stellar associations. However, only about similar to 1 per cent of the presently known exoplanets are found in these environments. To understand the roles of star cluster environments in shaping the dynamical evolution of planetary systems, we carry out direct N-body simulations of four planetary system models in three different star cluster environments with respectively N = 2k, 8k and 32k stars. In each cluster, an ensemble of initially identical planetary systems are assigned to solar-type stars with similar to 1M(circle dot) and evolved for 50 Myr. We found that following the depletion of protoplanetary discs, external perturbations and planet-planet interactions are two driving mechanisms responsible for the destabilization of planetary systems. The planet survival rate varies from similar to 95 per cent in the N = 2k cluster to similar to 60 per cent in the N = 32k cluster, which suggests that most planetary systems can indeed survive in low-mass clusters, except in the central regions. We also find that planet ejections through stellar encounters are cumulative processes, as only similar to 3 per cent of encounters are strong enough to excite the eccentricity by Delta e >= 0.5. Short-period planets can be perturbed through orbit crossings with long-period planets. When taking into account planet-planet interactions, the planet ejection rate nearly doubles, and therefore multiplicity contributes to the vulnerability of planetary systems. In each ensemble, similar to 0.2 per cent of planetary orbits become retrograde due to random directions of stellar encounters. Our results predict that young low-mass star clusters are promising sites for next-generation planet surveys, yet low planet detection rates are expected in dense globular clusters such as 47 Tuc. Nevertheless, planets in denser stellar environments are likely to have shorter orbital periods, which enhance their detectability.

Keyword :

planets and satellites: dynamical evolution and stability methods: numerical planets and satellites: formation galaxies: star clusters: general

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GB/T 7714 Cai, Maxwell Xu , Kouwenhoven, M. B. N. , Zwart, Simon F. Portegies et al. Stability of multiplanetary systems in star clusters [J]. | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY , 2017 , 470 (4) : 4337-4353 .
MLA Cai, Maxwell Xu et al. "Stability of multiplanetary systems in star clusters" . | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 470 . 4 (2017) : 4337-4353 .
APA Cai, Maxwell Xu , Kouwenhoven, M. B. N. , Zwart, Simon F. Portegies , Spurzem, Rainer . Stability of multiplanetary systems in star clusters . | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY , 2017 , 470 (4) , 4337-4353 .
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Clearing Residual Planetesimals by Sweeping Secular Resonances in Transitional Disks: A Lone-planet Scenario for the Wide Gaps in Debris Disks around Vega and Fomalhaut SCIE
期刊论文 | 2017 , 849 (2) | ASTROPHYSICAL JOURNAL | IF: 5.551
WoS CC Cited Count: 4
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Abstract :

Extended gaps in the debris disks of both Vega and Fomalhaut have been observed. These structures have been attributed to tidal perturbations by multiple super-Jupiter gas giant planets. Within the current observational limits, however, no such massive planets have been detected. Here we propose a less stringent "lone-planet" scenario to account for the observed structure with a single eccentric gas giant and suggest that clearing of these wide gaps is induced by its sweeping secular resonance. With a series of numerical simulations, we show that the gravitational potential of the natal disk induces the planet to precess. At the locations where its precession frequency matches the precession frequency the planet imposes on the residual planetesimals, their eccentricity is excited by its resonant perturbation. Due to the hydrodynamic drag by the residual disk gas, the planetesimals undergo orbital decay as their excited eccentricities are effectively damped. During the depletion of the disk gas, the planet's secular resonance propagates inward and clears a wide gap over an extended region of the disk. Although some residual intermediate-size planetesimals may remain in the gap, their surface density is too low to either produce superEarths or lead to sufficiently frequent disruptive collisions to generate any observable dusty signatures. The main advantage of this lone-planet sweeping-secular-resonance model over the previous multiple gas giant tidal truncation scenario is the relaxed requirement on the number of gas giants. The observationally inferred upper mass limit can also be satisfied provided the hypothetical planet has a significant eccentricity. A significant fraction of solar or more massive stars bear gas giant planets with significant eccentricities. If these planets acquired their present-day kinematic properties prior to the depletion of their natal disks, their sweeping secular resonance would effectively impede the retention of neighboring planets and planetesimals over a wide range of orbital semimajor axes.

Keyword :

stars: individual (Vega, Fomalhaut) protoplanetary disks planetary systems planet-disk interaction methods: numerical

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GB/T 7714 Zheng, Xiaochen , Lin, Douglas N. C. , Kouwenhoven, M. B. N. et al. Clearing Residual Planetesimals by Sweeping Secular Resonances in Transitional Disks: A Lone-planet Scenario for the Wide Gaps in Debris Disks around Vega and Fomalhaut [J]. | ASTROPHYSICAL JOURNAL , 2017 , 849 (2) .
MLA Zheng, Xiaochen et al. "Clearing Residual Planetesimals by Sweeping Secular Resonances in Transitional Disks: A Lone-planet Scenario for the Wide Gaps in Debris Disks around Vega and Fomalhaut" . | ASTROPHYSICAL JOURNAL 849 . 2 (2017) .
APA Zheng, Xiaochen , Lin, Douglas N. C. , Kouwenhoven, M. B. N. , Mao, Shude , Zhang, Xiaojia . Clearing Residual Planetesimals by Sweeping Secular Resonances in Transitional Disks: A Lone-planet Scenario for the Wide Gaps in Debris Disks around Vega and Fomalhaut . | ASTROPHYSICAL JOURNAL , 2017 , 849 (2) .
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